Detection and identification of pathologic alterations of the woman's low genital track (cervix of the uterus, vagina) involves a series of medical procedures including screening tests (pap-test), tissue examination with the aid of a microscope (colposcopy), biopsy sampling and histology. An abnormal pap-test is followed by colposcopy, where the vagina is opened with the aid of a speculum to allow tissue visualization with the aid of a microscope. In colposcopy, a number of diagnostic markers are applied topically, which alter the optical properties of the tissue, depending on the pathology. Particularly, application of 3-5% acetic acid solution provokes a reversible whitening of the abnormal tissue areas. It has been proved that the degree and the duration of the whitening effect correlates well with the neoplasia grade. The provoked contrast enhancement between normal and abnormal areas provide a valuable means for assisting colposcopic diagnosis and for locating abnormal areas for biopsy sampling and treatment. There is a considerable confidence for the diagnostic value of these diagnostic markers, which has been developed during the 70 years usage of these tests in the clinical practice.
The employment of marker-based in vivo tests as an alternative to the in vitro pap test for screening cervical pathology has increased in recent years. Marker-based in vivo tests employ a procedure similar to the colposcopy procedure, but typically are performed without the use of a microscope (colposcope). The vagina is opened with the aid of a speculum, which is followed by the application of acetic acid solution onto tissue surface and naked-eye monitoring of the marker-induced alterations in the color of the examined tissue. This technique is known as speculoscopy. In contrast to the pap-test, speculoscopy offers diagnostic results immediately, which enable the biopsy sampling and/or the treatment of the lesion even during the same consultation.
One main drawback of both colposcopy and speculoscopy arises from the fact that the quantity of applied marker is not standardized, while the marker administration means and procedures do not ensure its uniform application over the entire area of the examined tissue. In addition, the injection means employed obstruct the rear opening of the speculum, not allowing the monitoring of the effects provoked by the marker during its application and due to this fact critical diagnostic information is missed. Typically, an uncontrolled volume of the marker is applied either by washing the tissue with the aid of a cotton brush, moistened with acetic acid solution, or with the aid of a general purpose, hand held atomizer, which delivers a random quantity of the marker remotely. In some cases more than one injection are performed in a repetitive manner during the evolution of the acetowhitening phenomenon in order to achieve better contrast.
Clinical research, conducted by the inventors of the present invention, has shown that the monitoring of the effects provoked by the marker, during and after its application, has a great diagnostic value. The same research has also shown that the concentration and the quantity of the marker solution, applied onto the examined tissue are very critical since for a given pathology, different marker doses generate different optical effects, which may cause misdiagnosis. Particularly, for a given tissue pathology, an insufficient marker dose may cause in cancerous lesions an acetowhitening pattern similar to the one provoked by an optimum marker quantity in inflammations and in low grade neoplasias. Similarly, a high marker dose can cause an acetowhitening pattern in inflammations and low grade precancerous lesions typically found in cancerous lesions. Consequently, the lack of an arrangement enabling the standardization of the marker quantity applied onto the tissue surface may result in false positive and/or false negative results, thus, diminishing the diagnostic performance of these tests in terms of both sensitivity and specificity.
A number of prior art documents disclose various speculum arrangements with imaging and illuminations means integrated with a speculum, but they are characterized by the lack of injection means for applying uniformly a standardized quantity of a diagnostic marker, while simultaneously allowing for the inspection of the optical effects produced by the latter.
Such prior art documents include GB214913 and GB191027965. These documents disclose a vaginal speculum with incorporated fluid injection means. The purpose of fluid injection means, as described in these documents, is for washing the woman's low genital tract and it does not offer any standardization of the injected liquid. It is worth noticing that in these prior art documents, washing does not employ a diagnostic marker and therefore it is not intended to assist diagnosis and screening. More importantly, it does not allow for the visualization of the area of interest, since the whole inner space of the speculum is occupied by the fluid injection means and no free space is available allowing observation and insertion of treatment tools.
Other prior art documents disclose vaginal specula with integrated illumination means for illuminating the vagina. Such specula are disclosed, e.g., in documents GB1408382, U.S. Pat. Nos. 3,762,400, 3,851,642. These vaginal specula are intended for the medical examination of the vagina, but they are not accompanied with integrated fluid injection means, necessary for a diagnostic medical examination of the vagina wherein the uniform application of a standard volume of a diagnostic marker is necessary.
Other prior art described in documents WO9007299, WO9728753, U.S. Pat. Nos. 4,210,133 and 4,046,140, discloses vaginal specula with an integrated microscope or camera for observing and/or for capturing images of the cervical tissue. In the described implementations the microscopes or cameras are located within the blades not allowing the insertion of tools for biopsy sampling and treatment simultaneously with the inspection with the aid of a microscope or camera. In addition, the instruments disclosed in the foregoing documents do not allow the injection of diagnostic markers. Finally, the prior art document US20040122327 discloses an uteroscope arrangement including a panoramic lens for viewing the entire uterine cavity in one image that is mounted on an elongated shaft for insertion into the patient's uterus. One or more transparent inflatable balloons are mounted on the elongated shaft surrounding the optical imaging system. An instrument channel is provided in the shaft of the uteroscope for insertion of instruments, such as a suction tube, external to or in between the transparent inflatable balloons.